The present invention relates to the technical field of stereo, in particular, to a car stereo audio expanding method.
Typically, the stereo requires a pair of audios, and the distance between the audios is greater than 1 meter to be placed in front of the listener. The listener forms an equilateral triangle with the two audios, so as to establish a good effect and present a normal sound field. A good sound field performance can bring satisfaction.
Nowadays, the stereo expanding technology is based on a symmetrical listening environment that has a positive effect for TVs, computers and portable devices. However, the use environment of a car is not considered, and the application effect for the car is not good. For the reproduction of sound field of a car in the car audio, the sound field that should be is difficult to display due to the particularity of the car environment. Since the seat of the car is biased to one side, the distance between the listener and the left and right loudspeakers in the car environment is asymmetrical, and the listening angles of the left and right sides of the listener are several times different. Further, since there are many glass windows and the hardness of the glass is large, the sound is almost totally reflected, and the reflected sound is strong, so that the display of the sound field is affected.
For example, in the driving position (FIG. 1), the sound from the left loudspeaker has a direct sound Ld to the left ear of the driver, and a reflected sound Lr1+Lr2 reflected by the passengers door glass to the right ear of the driver. Similarly, the sound from the right loudspeaker has a direct sound Ld to the right ear of the driver and also a reflected sound Rr1+Rr2 reflected by the driver's door glass to the left ear. Since the direct sound is not far from the reflected sound, the difference in their sound is not so great that it seriously affects the display of the sound field.
The existing solution is to adding a delay on, the left sound channel to center the sound listened by the driver, and to confine the sound field within the front windshield. Although the existing stereo expanding technique can expand the sound to some extent, there will be some illusory and unreal feeling. And the known technique is to solve the problem of the asymmetry of the listening environment in the car by using the delay, but it does not solve the problem of the reflected sound of the door glass.